Coating method and facility for vehicle structural components

ABSTRACT

A manufacturing method and facility for applying a coating to vehicle structural components such as frames, provides unloading and stacking below the unloading station. Oscillation of the vehicle structural component in the coating liquid in the dip tank provides accelerated heat transfer, and also improves coating by eliminating air pockets. A bent carousel arm or a parallelogram linkage provides uniform coating action. Reverse travel sequencing minimizes space requirements.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a division of application Ser. No. 07/776,683 nowU.S. Pat. No. 5,152,840, filed Oct. 11, 1991, which is a continuation ofapplication Ser. No. 07/582,481 now abandoned, filed Sep. 14, 1990,which is a continuation-in-part of application Ser. No. 07/469,253 nowU.S. Pat. No. 5,061,528, filed Jan. 24, 1990, which is acontinuation-in-part of application Ser. No. 07/389,346 now U.S. Pat.No. 5,061,529, filed Aug. 3, 1989.

BACKGROUND AND SUMMARY

The present invention relates to continuing development efforts directedtoward manufacturing methods and facilities for applying a coating tovehicle structural components, including the application of a hot meltwax coating to vehicle frames for protection against rust and corrosion.

Parent Applications

The invention of the above noted '346 parent application arose duringdevelopment efforts directed toward reducing the high capital expense ofa manufacturing facility for coating vehicle structural components suchas frames. Vehicle manufacturers are more commonly requiring vendors andparts suppliers to have local onsite manufacturing or processingfacilities coordinating with the assembly operation of the vehiclemanufacturer. In the case of suppliers providing vehicle structuralcomponents such as frames, this requires erection of a coating facilityat each of the various satellite assembly facilities. However, erectionof multiple satellite coating facilities is not cost effective due tothe extremely high capital expense of same.

A vehicle frame is a generally flat longitudinal structural member whichin one exemplary size has a longitudinal length of about 178 inches, alateral width of about 42 inches, and a height of about 16 inches,though the dimensions may of course vary. Prior facilities for applyinga hot melt wax coating to such frames typically require buildings ofabout 2 million cubic feet, with 50,000 square feet of lateral area andover 60 feet in height. The frames are hung vertically and transportedto a dipping tank and dipped downwardly into the tank for coating theframe in the hot melt wax liquid, and then raised out of the tank.Hence, the building must be at least twice as high as the longitudinallength of the frame The tank volume is about 63,000 gallons. Thebuilding is heated by ovens or the like such that the heated air in thebuilding preheats the frames prior to dipping, to enhance the coatingduring the dip into the hot melt wax liquid tank. Preheating of theframes with air is inefficient and requires long preheat times. Thevertical hanging of the frames also requires large openings into and outof the building, causing significant heat loss and energy inefficiency.The construction cost of the building is high because of its specialrequirements. Furthermore, the building has no other use.

The invention of the '346 parent application addresses and solves theabove noted problems with a simple and effective manufacturing methodand facility. The invention of the '346 parent application reduces thebuilding volume by a factor of 10 or more, e.g. the new =building can bereduced to as little as 5% of the volume of the prior building. Theinvention of the '346 parent application also reduces the tank volumerequirements for the coating liquid to as little as 4%, e.g. to as lowas 2,000 gallons instead of the 63,000 gallons required for the abovenoted prior tank. This saves wax cost. The invention of the '346 parentapplication also significantly reduces the height requirement of thetank, e.g. from about 25 feet deep to about 25 inches deep. Thisdesirably solves problems of hydrostatic fluid pressure and leakagecaused thereby at the bottom of the tank. The construction cost of thebuilding is reduced by a factor of about 10 due to the reduced specialrequirements of the building and also due to reduced loading capabilityof the building due to special transport structure within the buildingin accordance with the invention of the '346 parent application forcarrying the vehicle structural components. The building is adaptable toother uses in the event of changing requirements. The transportmechanism and core within the building can be moved to other buildingsand locations.

The invention of the above noted '253 application provides amanufacturing method and facility with substantially reduced spacerequirements. The invention of the '253 application enables substantialportions of the processing mechanism to be placed external to the heatedhousing containing the coating tank. The invention of the '253application is also suitable to low volume, small quantity applications,if desired. In one embodiment, a tank housing has a specially configuredslot opening allowing passage therethrough of a cable of a winch pulleywhich rolls along a support beam of a jib crane as an arm pivots tolower and raise the frame into and out of a horizontal tank. The tank is24 feet long by 6 feet wide by 32 inches deep to provide a volume of 384cubic feet and holds 2,872 gallons, and has a surface area of 144 squarefeet. The volume of the shell housing over the tank is 2,262 cubic feet.In another embodiment, the tank extends partially circumferentiallyaround a central rotational hub and has an area of 536 square feet and avolume of 984 cubic feet and holds 7,358 gallons. The volume of theshell housing over the tank is 5,074 cubic feet.

Present Invention

The present invention arose during continuing development effortsrelating to the above noted manufacturing methods and facilities.

In one aspect, the invention provides unloading and stacking of vehiclestructural components below the unloading station.

In another aspect, the invention provides stroking and oscillation ofvehicle structural components in the dip tank, to accelerate heattransfer, and to improve coating by eliminating air pockets.

In another aspect, the invention provides a pivoted bent dip arm on arotary carousel affording improved dipping and uniform coating action.

In another aspect, the invention provides parallelogram linkageaffording improved dipping and uniform coating action.

In another aspect, the invention provides processing sequences andbidirectional travel paths reducing space requirements.

The invention also continues improvements in lower operating andmaintenance costs. The invention enables significant reductions inmanpower requirements. The invention enables the vehicle structuralcomponents to be automatically loaded, processed, unloaded, and stacked.The invention enables maintenance items to be located externally and atground level, which significantly reduces servicing costs.

BRIEF DESCRIPTION OF THE DRAWINGS Parent Applications

FIG. 1 is a top view of a manufacturing facility constructed inaccordance with the invention of the above noted '346 parentapplication.

FIG. 2 is a sectional view taken along line 2--2 of FIG. 1

FIG. 3 is an enlarged top view of a portion of the structure of FIG. 1.

FIG. 4 is a side view of the structure in FIG. 3.

FIG. 5 is a sectional view taken along line 5--5 of FIG. 4.

FIG. 6 is an enlarged view of a portion of the structure in FIG. 4.

FIG. 7 is a perspective view of the structure of FIG. 6.

FIG. 8 is an enlarged view of a portion of the structure in FIG. 4.

FIG. 9 is an end view of the structure in FIG. 8.

FIG. 10 is a perspective view of the structure in FIG. 8.

FIG. 11 is a sectional view taken along line 11--11 OF FIG. 4.

FIG. 12 is a sectional view taken along line 12--12 of FIG. 1.

FIG. 13 is a top view of an alternate embodiment of a manufacturingfacility constructed in accordance with the '346 parent application.

FIG. 14 is a sectional view taken along line 14--14 of FIG. 13.

FIG. 15 is a sectional view taken along line 15--5 of FIG. 13.

FIG. 16 is a sectional view taken along line 16--16 of FIG. 13.

FIG. 17 is a sectional view taken along line 17--17 of FIG. 13.

FIG. 18 is a top view of another embodiment of a manufacturing facilityconstructed in accordance with the '346 parent application.

FIG. 19 is a top view of another embodiment of a manufacturing facilityconstructed in accordance with the '346 parent application.

FIG. 20 is a side view of a manufacturing facility constructed inaccordance with the invention of the above noted '253 parentapplication.

FIG. 21 is a top view of a portion of the structure in FIG. 20.

FIG. 22 is a top view of an alternate embodiment of a manufacturingfacility constructed in accordance with the '253 parent application.

FIG. 23 is a side view of a portion of the structure of FIG. 22.

FIG. 24 is a top view of another embodiment of a manufacturing facilityconstructed in accordance with the '253 parent application.

FIG. 25 is a view taken along line 25--25 of FIG. 24.

FIG. 26 is a view taken along line 26--26 of FIG. 24.

Present Invention

FIG. 27 is a top view of a manufacturing facility constructed inaccordance with the present invention.

FIG. 28 is a sectional view taken along line 28--28 of FIG. 27.

FIG. 29 is a side view of a portion of the structure of FIG. 27.

FIG. 30 is a side view of another portion of the structure of FIG. 27.

FIG. 31 is an enlarged view of a portion of the structure of FIG. 30.

FIG. 32 is like FIG. 31 and shows another embodiment.

FIG. 33 is like FIG. 31 and shows another embodiment.

FIG. 34 is a top view of another embodiment of a manufacturing facilityconstructed in accordance with the invention.

FIG. 35 is a side view of a portion of the structure of FIG. 34.

FIG. 36 is an end view of a portion of the structure of FIG. 35.

FIG. 37 shows an alternate embodiment of a portion of the structure ofFIG. 35.

FIG. 38 shows another alternate embodiment of a portion of the structureof FIG. 35.

FIG. 39 shows another alternate embodiment of a portion of the structureof FIG. 35.

FIG. 40 is a sectional view taken along line 40--40 of FIG. 39.

FIG. 41 is like FIG. 35 and shows another embodiment.

FIG. 42 is like FIG. 35 and shows another embodiment.

FIG. 43 shows another alternate embodiment of a portion of the structureof FIG. 35.

FIG. 44 shows another alternate embodiment of a portion of the structureof FIG. 35.

FIG. 45 is a top view of another embodiment of a manufacturing facilityconstructed in accordance with the invention.

FIG. 46 is a sectional view taken along line 46--46 of FIG. 45.

FIG. 47 is a sectional view taken along line 47--47 of FIG. 45.

FIG. 48 is a top view of a portion of the structure of FIG. 47.

FIG. 49 is a side view of a portion of the structure of FIG. 45.

FIG. 50 is a sectional view taken along line 50--50 of FIG. 49.

FIG. 51 is a top view of another embodiment of a manufacturing facilityconstructed in accordance with the invention.

FIG. 52 is a top view of another embodiment of a manufacturing facilityconstructed in accordance with the invention.

DETAILED DESCRIPTION Parent Applications

FIG. 1 shows a manufacturing facility 20 with substantially reducedspace requirements for applying a coating to vehicle structuralcomponents such as frames 22, 24, and the like. The facility includes abuilding 26 housing a central rotary carousel 28 having a central hub 30rotatable about a vertical axis and having a plurality of arms 32, 34,etc. thereon. Building 26 also houses a loading station 36, a coatingstation 38 having coating liquid 40 in tank 42, and an unloading station44, all spaced peripherally around hub 30 such that rotation of hub 30moves the arms to the various stations. Building 26 also houses apreheat wash station 46, a rinse station 48, and a post heat dripstation 50. Preheat wash station 46 includes a tank 52 with a washliquid 54 at an elevated temperature. Rinse station 48 includes a tank56 with a rinse liquid 58 at an elevated temperature. The preheat washand rinse stations preheat the frame by liquid heat transfer, to enhancethe hot melt wax coating at station 38 when the frame is dipped into thehot melt wax coating liquid 40, to be described.

Counterclockwise rotation of hub 30 moves arm 32 to loading station 36as shown in FIG. 1, for attaching frame 22 to arm 32, to be described.Further counterclockwise rotation of hub 30 moves arm 32 to preheat washstation 46, and then to rinse station 48, and then to coating station38, and then to post heat drip station 50, and then to unloading station44 for detaching frame 22 from the arm.

Arm 32 moves downwardly, FIG. 2, at loading station 36 to engage frame22 and then moves upwardly to lift the frame and carry the frame duringrotation of hub 30. The arm moves downwardly at each of stations 46, 48and 38 to lower the frame into the liquid in the respective tank, andthen moves upwardly to raise the frame out of such liquid in therespective tank. The arm moves downwardly at unloading station 44 todisengage the frame and then moves upwardly and rotates to loadingstation 36, to begin the next cycle.

Arm 32 swings in an arc about pivot point 60 at hub 30, and is actuatedbetween its upwardly raised position as shown in phantom line and itsdownwardly lowered position as shown in solid line by a hydrauliccylinder 62, or alternatively is pneumatically actuated, or is raisedand lowered by a cable, chain, or the like. Frame 22 at loading station36 is attached in a generally horizontal position to arm 32. The frameis likewise detached in a generally horizontal position from the arm atunloading station 44. The frame is lowered by the arm into therespective tanks at stations 46, 48 and 38 in a generally horizontalposition in the respective tank. The horizontal loading, dipped andunloading positions of the frame are all substantially coplanar.

Frame 22 has a longitudinal extent of a given length. As seen in FIG. 2,building 26 has a height to roof 64 substantially less than twice thelength of frame 22. The transport mechanism provided by carousel 28moves frame 22 through stations 36, 46, 48, 38 and 44 such that thelongitudinal extent of frame 22 is substantially horizontal. The raisingand lowering of frame 22 into and out of the tanks at stations 46, 48and 38 defines a travel path having a vertical height substantially lessthan twice the length of the frame. Building 26 has a sidewall 66 withan entrance opening 68 therethrough, FIGS. 1, 2 and 11, at loadingstation 36, and an exit opening 70 therethrough at unloading station 44.Frame 22 is passed longitudinally through such openings in a generallyhorizontal position into and out of building 26, such that openings 68and 70 have minimum dimensions, to minimize heat loss from the building.

At drip station 50, uncoated excess liquid is allowed to drip from theframe. Additionally or alternatively, uncoated excess liquid is allowedto drip from the frame above tank 42 at coating station 38. The amountof pivoting of the transport arm varies the tilt angle, to provide anadjustable drip angle of the frame. This is particularly desirablebecause it enables a selectively chosen drip angle, which in someinstances may be vertical, or in other instances at a diagonal anglerelative to horizontal. The latter is preferred to prevent drips fromone of the lateral cross pieces of the frame from dripping onto anotherlateral cross piece therebelow. The pivoted transport arm thus moves theframe through the coating station into and out of contact with thecoating liquid and raises the frame after such coating to a tiltedposition such that the longitudinal extent of the frame is tilted at anangle relative to horizontal.

Hands 72, 74, 76, 78, FIGS. 3 and 4, extend from arm 32 and have fingers80, 82, 84, 86, 88, 90, 92, 94 engaging frame 22. Frame 22 is attachedto the fingers at loading station 36. A conveyance mechanism provided bycontinuous belt conveyor 96 carries frame 22 longitudinally horizontallythrough flexible hanging leaves 98 at opening 68 in building wall 66 toloading station 36. Conveyor 96 carries frame 22 rightwardly, FIGS. 1-4,to a first position. Arm 32 is swung downwardly, with at least some ofthe noted fingers moving downwardly past and below frame 22. Conveyor 96then carries frame 22 further rightwardly, advancing frame 22 to asecond position above the last mentioned fingers, such that uponswinging arm 32 upwardly, such last mentioned fingers engage theunderside of frame 22 and lift same.

Frame 22 is a generally flat planar member having a pair of longitudinalsides 100 and 102, FIG. 3, and a plurality of lateral cross pieces suchas 104, 106, 108, 110, 112. Fingers 80 and 84 engage the underside ofcross piece 104. Fingers 82 and 86 engage the underside of longitudinalsides 100 and 102, respectively. Fingers 88 and 92 engage the undersideof cross piece 112. Fingers 90 and 94 engage the top side oflongitudinal sides 100 and 102, respectively. The noted engagementlocates the longitudinal sides of the frame and the respective crosspieces of the frame, to precisely locate the frame both longitudinallyand laterally.

The fingers are formed with a knife edge laterally crossing therespective portion of the frame, for example as shown at knife edges 114and 116 for respective fingers 80 and 82 in FIGS. 6 and 7, and knifeedges 118 and 120 for respective fingers 88 and 90 in FIGS. 8-10. Thelower fingers 80, 84, 88, 92 are slightly angled, such that when arm 32is in the lowered position, the lower fingers tilt upwardly leftwardlyand engage only an edge of the frame to provide only point contacttherewith, to enhance the coating of the frame. The lateral lowerfingers 82 and 86 and the lateral upper fingers 90 and 94 extendlaterally across the longitudinal sides of the frame and are likewiseangled, as shown in FIG. 7 for finger 82, and in FIGS. 9 and 10 forfinger 90, to also provide only point contact with the frame, to enhancecoating of the frame. The noted lower longitudinal fingers are tiltedsufficiently relative to the respective hands such that arm 32 may belowered to a position slightly beyond horizontal, FIG. 4, and the lowerfingers will still engage and lift frame 22. In a further embodiment,finger 90 has an upwardly extending portion 121 facilitating stacking offrames. In this latter embodiment, two or more frames are carried oncarousel arm 32, such that two or more frames are dipped during eachdipping step, etc. In this embodiment, edge 120 does not engage the topof the frame therebelow, but rather locates the siderails of the frameoutboard thereof, and edge 121 is spaced slightly inwardly of the framesiderail.

Stationary V-shaped structure 122, FIG. 11, is provided at loadingstation 36 and spaced above conveyor 96 and is engaged by arm 32 duringdownward swinging of the arm to guide and locate the arm relative toconveyor 96 and frame 22. Conveyor 96 has a plurality of cones 124, 126,128, 130, etc., thereon, with angled bevel surfaces forming knife edgessuch as 132, FIGS. 3 and 5, which extend along a diagonal angle toprovide point contact with the frame. Some of the cones such as cones126 and 130 engage the longitudinal sides of the frame, and others ofthe cones such as cones 124 and 128 engage lateral cross pieces of theframe. The cones space the frame above conveyor 96 and precisely locatethe frame both longitudinally and laterally. In an alternate embodiment,the frame has a plurality of holes in the underside thereof, andconveyor 96 has a plurality of cones extending upwardly partiallythrough such holes and spacing the frame above the conveyor andprecisely locating the frame both longitudinally and laterally.

Unloading at station 44 is comparable but reversed in sequence fromloading at station 36. A conveyor 134 is provided like conveyor 96. Thetransport arm of the carousel is lowered to lower the frame onto thecones on the conveyor. The above noted knife edges and angles on thefingers provide the noted point contact with the frame and minimizemarring of the coating on the frame. In most applications, there is nomarring because the hot melt wax coating heals itself, which healing isfacilitated by the noted point contact, which minimizes the area whichmust be healed by continued flow of the hot melt wax coating afterdisengagement of the frame by the fingers. The above noted beveledsurfaces and knife edges such as 132, FIG. 5, of the cones on theconveyor and the angles thereof desirably provide only point contactwith the coated frame on exit conveyor 134. After the pivot arm of thecarousel is lowered such that the frame now rests on the cones onconveyor 134, the latter moves slightly to partially advance the frameto allow clearance of the lower fingers, and the pivot arm is thenraised upwardly, whereafter conveyor 134 carries the frame outwardlythrough opening 70 of the building. Opening 70 is not provided with thehanging flexible leaves such as 98 of entrance opening 68, because suchleaves would drag across and mar the coating on the frame. Instead,opening 70 is provided with a quick acting guillotine door 136, FIG. 12,actuated by pneumatic cylinder 138 to quickly move vertically upwardlyand downwardly. This minimizes heat loss from the building.

FIG. 13 shows a further embodiment, and like reference numerals are usedfrom the above FIGS. where appropriate to facilitate clarity. Preheatwash and rinse stations 140 and 142 are external of building 144.Preheat wash station 140 includes a tank 146, a heater 148, a pump 150supplying heated wash liquid to spray nozzles 152, and a return filter154. Rinse station 142 is comparable for rinse liquid. Conveyor 96conveys the frame horizontally longitudinally through stations 140 and142 to provide liquid heat transfer to the frame, and then moves theframe into building 144. This movement is along the direction of thelongitudinal extent of the frame. The frame is attached to pivot arm 32as above described, and the arm swings upwardly to lift the frame fromthe conveyor 96.

Coating station 38 of FIG. 1 is replaced by a coating station 154 inFIG. 13 with a tank 156 which is substantially laterallycircumferentially expanded to extend along a significant portion of theinner periphery of the building around hub 30. In FIG. 13, tank 156 hasa semicircular shape when viewed from above. Transport arm 32 lowers theframe into and out of tank 156, as above. Transport arm 32 also movesthe frame horizontally through tank 156 in a direction transverse to thelongitudinal extent of the frame. The lowering and raising of the frameinto and out of the tank defines a travel path having a vertical heightsubstantially less than twice the length of the frame, as before. Aheater 158 and pump 160 are provided for heating and pumping coatingliquid 162 to tank 156.

Building 144 has differing heights at loading station 36 and the centralportion of coating station 154. At loading station 136, the buildingmust be high enough to allow arm 32 to pivot upwardly to lift the framefrom conveyor 96. However, in the central portion of coating station154, as shown on the right side of FIG. 14, arm 32 need only movehorizontally laterally, and hence there is no need for any greaterbuilding height other than a small clearance for arm 32 above the tank.The roof of building 144 along this central portion of coating station154 is provided by access doors 164. At the beginning of coating station154, an increased building height is necessary as shown at roof 166 atthe left side of FIG. 14, to accommodate movement of arm 32 in an upwardposition over tank 156 and then downward movement of arm 32 to lower theframe into tank 156. The building likewise has a higher roof at the endof coating station 154. The building thus has a first lower height atroof access door 164 over the middle of tank 156, and second higherheights as at roof 166 at the ends of the tank to permit downward andupward swinging of arm 32 to lower and raise the frame into and out ofthe tank. The unloading station may be provided within the building, asin FIG. 1, or an external loading station 168 may be provided with theframes remaining in a horizontal position but stacked vertically, andthen periodically removed by a forklift 170 or the like. Building 144has an external recess 169 formed in the periphery thereof at whichunloading station 168 is located.

In a further embodiment, a cam track is provided in the building toassist or eliminate the pivot arm actuators such as 62. FIG. 15 shows acam track 172 extending at least partially peripherally around centralhub 30. Arm 32 has a roller 174 engaging and rolling along the cam trackduring rotation of hub 30 such that arm 32 is lowered and raisedaccording to the camming profile of the cam track. The cam track has aV-shape at loading station 136 such that roller 174 rides down the V tolower the arm to engage the frame. At coating station 154, the cam trackmay be provided by the upper lip 176 of the tank having high lobes atthe beginning and the end of the tank, and having an extended low lobealong the central portion of the tank. The horizontal circumferentiallength of the low lobe portion of the cam surface controls the length ofhorizontal travel of the frame in coating liquid 162 in tank 156 duringrotation of hub 30, to control coating of the frame.

FIG. 18 shows another embodiment, and uses like reference numerals fromthe above FIGS. where appropriate to facilitate clarity. A servicingstation 180 is spaced along the periphery of hub 30. Building 182 has anopening 184 at station 180. The carousel pivot arm is movable to alowered position at servicing station 180, passing through opening 184in building 182 externally of the building to external servicinglocation 180 for servicing of the transport pivot arm. The arm ismovable to an upward position at servicing station 180 remaining withinbuilding 182 and bypassing external servicing location 180 and insteadpassing within building 182 to the next station therein upon rotation ofhub 30. Building 182 has an external recess 186 formed therein atservicing station 180 providing the external location for servicing ofthe pivot arm. Thus, when servicing is desired, the pivot arm is swungdownwardly through opening 184 to permit servicing, and then pivotedback upwardly through opening 184 when the servicing is completed. Thisallows servicing of the pivot arm externally of the building, which isdesirable because the servicing technician can remain outside thebuilding and not have to work in the elevated temperatures within thebuilding. When servicing is not desired, the pivot arm merely remains inits upward pivoted position at station 180 without passing throughopening 184.

FIG. 19 shows another embodiment, and like reference numerals are usedfrom the above FIGS. where appropriate to facilitate clarity. Building188 has an increased number of stations which may provide variousdesired combinations of preheat washing, rinsing, coating, and drippingbetween loading station 36 and unloading station 44. The carousel at thecore of the building is supported independently of the building, and maybe moved to different locations and buildings as desired.

Numerous alternatives are possible. For example, instead of conveyingthe frames to the loading station with a conveyor, other conveyancemechanisms may be used, such as a cart, a shuttle, loading from beneathrather than through a sidewall opening, etc. While plural transportpivot arm assemblies are shown, single arm assemblies may of course beused. A facility with a single station in the building may also be used,to provide only coating within the building, and to provide loading andunloading externally of the building, as well as preheating if desired.The facilities and methods disclosed may also be used in cold coatingprocesses. In further embodiments, the motor drive for the hub may beprovided at the hub within the building, or may be provided externallyof the building with an outer ring for mechanical advantage enabling asmaller motor and saving the motor from the harsh environment andelevated temperatures within the building. While a single frame perpivot arm of the carousel is shown, each arm may carry and dip more thanone frame at a time. For example, one frame may be carried above thearm, and another frame below the arm. Further alternatively, multipleframes may be stacked, and carried by an arm.

FIGS. 20 and 21 show a manufacturing facility 200 with substantiallyreduced space requirements for applying a coating to vehicle structuralcomponents such as frame 202. A coating station is provided by a tank204 containing coating liquid 206. A jib crane 208 is provided by agenerally vertically extending hub 210 rotational about a generallyvertical axis 212, a support beam 214 extending horizontally from hub210, and a winch pulley 216 translatable on rollers 217 along beam 214and having a cable 218 extending downwardly. Winch pulley 216 includes amotor (not shown) for lowering and raising cable 218. A carrier arm 220is provided for carrying frame 202, comparable to above described arms32, 34, etc. in the '346 parent application, and is pivotally mounted tohub 210 below beam 214. Cable 218 is attached to arm 220 for moving thearm through the coating station. Arm 220 has depending hands such as 222and 224, comparable to above described hands 72, 74, 76, 78, and fingerssuch as 226 and 228, comparable to above described fingers 80, 82, 84,86, 88, 90, 92, 94, engaging frame 202.

Arm 220 pivots at mount 230 on hub 210 about a generally horizontalpivot axis 232 transverse to the direction of translation of pulley 216along beam 214. As cable 218 is let out from winch pulley 216, arm 220pivots downwardly about pivot axis 232, and pulley 216 translatesrightwardly along beam 214 away from hub 210. The downward pivoting ofarm 220 dips frame 202 into coating liquid 206 in tank 204. As cable 218is retracted back up to pulley 216, arm 220 pivots upwardly about pivotaxis 232, and pulley 216 translates leftwardly along beam 214 toward hub210. The upward pivoting of arm 220 raises frame 202 out of coatingliquid 206 in tank 204. It is preferred that pulley 216 be freelytranslatable on rollers 217 along beam 214. As arm 220 pivots downwardlyand upwardly, it will cause right and left translation of the pulleyalong the beam, as cable 218 remains in a vertical position to supportthe weight of arm 220 and frame 202 as pulled downwardly by gravity. Inanother embodiment, the pulley can be further motorized to mechanicallydrive the pulley right and left along the beam. In a further embodiment,translation of the pulley along the beam can be limited, or the pulleycan be located at a stationary position on the beam, and cable 218 willmove through various angles relative to vertical as arm 220 pivotsdownwardly and upwardly.

A shell housing 234 is above and encloses tank 204. Housing 234 has adoor 236 permitting entry and exit of arm 220 and frame 202. Housing 234has a slot 238 through which cable 218 extends. The slot has a givenconfiguration and extension permitting translation of cable 218therealong as pulley 216 translates along beam 214. Slot 238 has agenerally L-shaped configuration when viewed from above, FIG. 21. Afirst portion 240 of the slot extends toward and away from hub 210. Asecond portion 242 of the slot extends transversely to portion 240.Cable 218, arm 220 and frame 202 enter housing 234 in response torotation of hub 210 about vertical axis 212. Cable 218, arm 220 andframe 202 enter housing 234 along a direction transverse to thedirection of lowering and raising of frame 202 into and out of tank 204.Housing 234 has a top wall 244 in which slot 238 is formed, and has asidewall 246 extending downwardly from the top wall. The sidewall has anopening 248 therein covered by door 236 mounted to the housing at hinges250, 252 and 254. Arm 220 and frame 202 enter the housing throughopening 248 in the housing sidewall. Arm 220 translates frame 202horizontally during rotation of hub 210 to a position above tank 204.Arm 220 then lowers frame 202 into the tank to a generally horizontalposition for coating of the frame. Arm 220 then raises the frame out ofthe tank, and hub 210 is rotated in the opposite direction such that arm220 and frame 202 exit the housing through opening 248 in the sidewall.Movement of frame 202 in the coating station in housing 234 defines atravel path having a vertical height substantially less than twice thelength of frame 202.

FIGS. 22 and 23 show a further embodiment and use like referencenumerals from FIGS. 20 and 21 where appropriate to facilitateunderstanding. Tank 260 and

2 extend partially circumferentially around hub 210. Frame 202 istranslated horizontally through tank 260, in a direction transverse tothe longitudinal extent of the frame, in response to rotation of hub 210about vertical axis 212. The slot in the top wall of the housing furtherincludes an arcuate portion 264 along and above tank 260 and extendingpartially circumferentially around hub 210 and through which cable 218extends when frame 202 is in its downwardly lowered position in tank260. Cable 218 is translated along arcuate slot portion 264 as hub 210rotates about vertical axis 212. External to the housing are a loadstation 266 and an unload station 268, for loading and unloading framesby a fork lift truck 270 or the like. FIG. 23 shows an alternate door272 for covering opening 274 in the sidewall of the housing. The door isnot hinged as in FIG. 20, but instead slides along tracks 276 and 278between a rightward open position as shown, and a leftward closedposition.

FIGS. 24-26 show a further embodiment and use like reference numeralsfrom above where appropriate to facilitate understanding. Housing 280 isextended all the way around hub 210 and encloses load and unloadstations 266 and 268. Tank 282 only extends partially circumferentiallyaround the hub. The frames enter and exit the housing on conveyors 284and 286 as in the '346 parent application. The housing has a sidewall288, FIG. 25, with an entrance opening 290 therethrough at loadingstation 266, and has hanging flexible leaves 292, as in the parentapplication, FIG. 11. Sidewall 288 of the housing has an exit opening294, FIG. 26, therethrough with a quick acting guillotine door 296actuated by pneumatic cylinder 298 to quickly move vertically upwardlyand downwardly, as in the '346 parent application, FIG. 12. The framespass longitudinally through the entrance and exit openings in agenerally horizontal position into and out of the housing. Openings 290and 294 have minimum dimensions, to minimize heat loss from the housing.Also, multiple frames may be carried by an arm.

In other embodiments, the facility has different numbers of arms and/ortanks, including wash and rinse tanks as noted above.

Present Invention

FIG. 27 shows a manufacturing facility including a building 300 housinga transport mechanism 302 provided by a rotary carousel 304 having acentral hub 306 rotatable about a vertical axis 308 and having aplurality of arms 310 each carrying one or more stacked vehiclestructural components 312, such as frames, each having a longitudinalextent of given length. The facility includes a loading station 314, acoating station 316 including a dip tank 318 containing coating liquid320, FIG. 28, a drip station 322, and an unloading station 324. Arms 310are pivoted to hub 306 at trunions 326, FIG. 28, to pivot about ahorizontal pivot axis 328 and swing in an arc in a vertical plane.

Vehicle structural component 312 is loaded to transport mechanism 302 atloading station 314, and then transported by transport mechanism 302 tocoating station 316. Vehicle structural component 312 is moved throughcoating station 316 in a horizontal position such that the longitudinalextent of the vehicle structural component is substantially horizontal,as in the above noted parent applications. The vehicle structuralcomponent is then transported through drip station 322 to unloadingstation 324 and is unloaded in a generally horizontal position below theunloading station, FIG. 29. Additional vehicle structural components aretransported to the unloading station and unloaded and stacked in ahorizontal position on the vehicle structural component therebelow toprovide a stack of horizontal vehicle structural components stackedvertically and disposed below the unloading station.

A given number of vehicle structural components are stacked below theunloading station, and upon completion of the stacking, the stack ofvehicle structural components is transported from below the unloadingstation. For example, FIG. 30 shows six vehicle structural componentswhich had been stacked below the unloading station in FIG. 29 and thentransported rightwardly externally of building 300 to the position shownin FIG. 30. In the embodiment in FIGS. 27-30, the loading station,coating station and unloading station are at ground level, and anexcavation 330, FIGS. 29 and 30, is provided below ground level at theunloading station. The vehicle structural components are stacked inexcavation 330 below the unloading station.

In FIG. 29, a stacking station 332 in excavation 330 includes a stackingmechanism 334, provided by a scissors jack. The stacking mechanism canroll left and right on wheels 336 rolling on horizontal track 338 aspulled by tow rope 340 on motor driven pulleys 342. Vehicle structuralcomponent 312 is detached from transport mechanism arm 310 and loweredin a horizontal position at stacking station 332 by stacking mechanism334 below unloading station 324. A second vehicle structural component,which had been attached to the transport mechanism at the loadingstation and transported through the coating station and the dripstation, is stacked in a horizontal position on the first vehiclestructural component and detached from arm 310 of the transportmechanism. The first and second vehicle structural components arelowered in the horizontal position at stacking station 332 belowunloading station 324. A third vehicle structural component, which hadbeen attached to the transport mechanism at the loading station andmoved through the coating station and the drip station, is transportedto the unloading station and stacked on the second vehicle structuralcomponent and detached from arm 310 of the transport mechanism. Thefirst, second and third vehicle structural components are lowered in ahorizontal position at stacking station 332 below unloading station 324.The above steps are repeated a desired number of times to provide aplurality of horizontally extending vehicle structural componentsstacked vertically at stacking station 332 below unloading station 324.

The scissors jack provides a stacking mechanism which is raised toengage vehicle structural component 312 and lift same from fingers 344of hands 346 of arm 310 of the transport mechanism. Stacking mechanism334 is then rolled rightwardly through a distance at least as long asfingers 344, FIG. 29, to detach vehicle structural component 312 fromthe transport mechanism, and to enable arm 310 of the transportmechanism to swing back upwardly and rotate clockwise to loading station314, FIG. 27. Stacking mechanism 334 is then lowered and movedhorizontally leftwardly to return to an alignment position to receivethe second vehicle structural component such that the first vehiclestructural component engages the second vehicle structural componentthereabove at the unloading station and lifts the second vehiclestructural component from fingers 344 of hands 346 of arm 310 of thetransport mechanism, to detach the second vehicle structural componentfrom the transport mechanism. Stacking mechanism 334 is then movedhorizontally rightwardly, and arm 310 is pivoted upwardly, and stackingmechanism 334 is lowered and moved horizontally leftwardly to return toan alignment position to receive the third vehicle structural componentsuch that the second vehicle structural component engages the thirdvehicle structural component at the unloading station and lifts thethird vehicle structural component from the transport mechanism todetach same. The above steps are repeated a desired number of times toprovide a desired number of stacked vehicle structural components belowunloading station 324.

Arm 310 moves downwardly at loading station 314 to engage vehiclestructural component 312, and then moves upwardly at the loading stationto lift the vehicle structural component and carry same during rotationof hub 306. Arm 310 is moved downwardly at the coating station to dipthe vehicle structural component into coating liquid 320, FIG. 28, andthen upwardly at the coating station, and then downwardly at unloadingstation 324 to disengage the vehicle structural component as stackingmechanism 334 engages the vehicle structural component. Arm 310 is thenmoved upwardly at the unloading station, and hub 306 is rotated to movearm 310 to loading station 314, to repeat the cycle.

Arm 310 is moved downwardly at unloading station 324 until stackingmechanism 334 engages the vehicle structural component. In oneembodiment, arm 310 continues to move downwardly with a slight amount ofovertravel to disengage the vehicle structural component, whereafterstacking mechanism 334 moves horizontally rightwardly, whereafter arm310 moves upwardly at unloading station 324, and hub 306 rotates to movearm 310 to loading station 314. In another embodiment, arm 310 movesdownwardly at unloading station 324 to a given position, and stackingmechanism 334 moves upwardly and engages the vehicle structuralcomponent and lifts the vehicle structural component from the arm,whereafter stacking mechanism 334 moves horizontally, and arm 310 movesupwardly at unloading station 324, and hub 306 is rotated to move arm310 to loading station 314.

The frames are stacked and aligned with guide pins 348, FIG. 31. Anothertype of guide pin 350, FIG. 32, includes a tapered frusto-conicalsurface 352 supporting and spacing the upper vehicle structuralcomponent above the lower vehicle structural component. Another type ofstacking and spacing pin 354 is shown in FIG. 33.

An oscillating mechanism is provided for oscillating vehicle structuralcomponent 312 in coating liquid 320 in dip tank 318. This acceleratesheat transfer, and also improves coating by eliminating air pockets. Arm310 is raised and lowered by a cable 356 extending around a pulley 358and driven by a cable winch pulley drive 360. Pulley 358 iseccentrically mounted on a wheel 362 on hub 306. Pulley 358 is strokedupon rotation of wheel 362, to in turn stroke cable 356, and in turnstroke arm 310 up and down, and in turn oscillate vehicle structuralcomponent 312 up and down in coating liquid 320 in tank 318. In anotherembodiment, pulley 358 is not oscillated, but instead the winch pulleydrive 360 is operated in periodic forward and reverse directions tostroke cable 356 and provide oscillation of vehicle structural component312 in tank 318.

Hub 306 includes a lower annular flange 364 having a toothed outerperiphery to provide a gear driven by drive gear 366 of drive motor 368.The underside of flange 364 is supported on bearings 370 mounted tolower support trunions 372. Hub 306 rotates about a center verticalstalk 374 and is guided by bearings 376 mounted to trunions 378 on theundersurface of flange 364.

In FIG. 34, a transport mechanism 400 is provided by a rotary carousel402 having a central hub 406 rotatable about a vertical axis 408 andhaving a plurality of arms 410, FIG. 35, pivotally mounted to hub 406 topivot about horizontal pivot axis 412 and swing in an arc in a verticalplane. A plurality of rigid stationary spokes provided by support beams414 extend radially outwardly from hub 406 and are connected adjacenttheir outer ends by a circumferential support bar 416, FIG. 34, whichrides on bearings 418, FIG. 35, supported by trunions 420 mounted to thesidewall of building 422. Arm 410 is raised and lowered by a cable 424extending around pulley 426 journaled to support beam 414. The pulley isdriven by winch pulley drive 428 at the outer end of support beam 414.One or more stacked vehicle structural components 430 are carried on arm410 at fingers 432 of hands 434, as above. The carousel rotates fromloading station 401a to preheat wash station 401b to preheat rinsestation 401c to coating station 401d to drip station 401e to unloadingstation 401f, and then back to the loading station to repeat the cycle.

An oscillating mechanism 436, FIG. 35, engages the outer end of arm 410and oscillates arm 410 up and down about pivot point 412 to move vehiclestructural components 430 up and down in coating liquid 438 in dip tank440. The oscillating mechanism is provided by an eccentric cam 442 onshaft 444 driven by motor 446 and engaging roller 448, FIGS. 35 and 36,mounted to the underside of arm 410 by trunion 450. Rotation of cam 442by motor shaft 446 strokes the outer end of arm 410 up and down.

In another embodiment, the oscillating mechanism is provided by mountingwinch pulley drive 428, FIG. 35, on an extensible and retractablecylinder 452, FIG. 37, at the end of support beam 414. FIG. 37 alsoshows a longer support beam 414 extending externally of building 422.Extension and retraction of cylinder 452 strokes winch pulley 428horizontally rectilinearly back and forth to stroke cable 424, andoscillate arm 410 up and down while vehicle structural components 430are in tank 440. In another embodiment, winch pulley 428 is alternatelydriven in opposite directions to raise and lower cable 424 and providethe noted oscillation.

FIG. 38 shows a further embodiment including a pair of guide bars 454and 456 extending downwardly from and on opposite sides of arm 410 forengaging guide surfaces 458 and 460 straddling tank 440 to guide andcenter the vehicle structural components as they are dipped into coatingliquid 438 in tank 440. Guide bars 462, FIG. 35, may also be mounted tosupport beam 414 to locate arm 410 at the upper end of its swing arctravel and hold same in place as hub 406 rotates.

FIG. 39 shows another oscillating mechanism 464 including a motor 466driving a shaft 468 having a link 470 pivotally connected to rod 472 tomove holder 474 up and down along track 476, FIG. 40. Holder 474receives the outer end of arm 410 to move the latter up and down, andoscillate vehicle structural components 430 in tank 440. Holder 474includes sloped guidewalls 478 for centering and retaining arm 410.

In FIG. 41, the rotary carousel of the transport mechanism has a bentarm 480 having a first portion 482 extending upwardly and a secondportion 484 extending outwardly from first portion 482 and forming anelbow 486 therewith at a given angle 488. Arm 480 is pivoted at portion482 to hub 406 to swing in an arc about horizontal pivot axis 489. Thearm includes a plurality of hands 490 extending downwardly from portion484 and having lower fingers 492 engaging one or more stacked vehiclestructural components 430. Downward swinging of arm 480 lowers vehiclestructural components 430 into tank 440. Portion 484 of arm 480 isspaced above the horizontal plane of pivot axis 489 when vehiclestructural components 430 are in tank 440. Angle 488 of elbow 486 isselected such that pivot axis 489 is substantially coplanar with thecenter of the stack of vehicle structural components 430. This providesmore nearly vertical travel of vehicle structural components 430 intoand out of tank 440 as the vehicle structural components are beingdipped in coating liquid 438. This in turn provides more uniform coatingby minimizing the differential travel path length and time between innerand outer ends 430a and 430b of the vehicle structural components. Thestraightening of the swing arc in tank 440 to a more nearly verticaldirection also enables a tank of smaller radial length, with reducedclearances 494 and 496 between the tank walls and the ends 430a and 430bof the vehicle structural components.

In FIG. 42, triangular shaped arm 500 carries vehicle structuralcomponents 430. Parallelogram linkage 502 pivotally mounts arm 500 tohub 406 such that the parallelogram linkage pivots about hub 406 andswings up and down in an arc in a vertical plane and such that arm 500moves up and down in the vertical plane along a travel path including agiven range of motion immediately above dip tank 440 which issubstantially parallel to vertical axis 408. Vehicle structuralcomponents 430 have a longitudinal extent of given length betweenlongitudinal ends 430a and 430b . Downward pivoting and swinging ofparallelogram linkage 502 and consequent downward movement of arm 500lowers vehicle structural components 430 into tank 440 in a generallyhorizontal position such that the longitudinal extent of the vehiclestructural components is substantially horizontal. Upward pivoting andswinging of parallelogram linkage 502 and consequent upward movement ofarm 500 raises vehicle structural components 430 out of tank 440 in agenerally horizontal position. The lowering and raising into and out oftank 440 is in the noted given range of motion substantially parallel tovertical axis 408 such that both longitudinal ends 430a and 430b ofvehicle structural components 430 enter tank 440 and coating liquid 438substantially simultaneously and leave the tank and liquid substantiallysimultaneously and have substantially the same travel path length andtime in the coating liquid in the tank. This provides uniform coatingbecause outer end 430b does not enter coating liquid 438 later thaninner end 430a, nor does outer end 430b have a longer swing arc travelpath in coating liquid 438 than inner end 430a. This also enables thenoted minimum clearances 494 and 496, and hence a minimum radial lengthtank 440, since the latter does not have to accommodate the horizontalcomponent otherwise present in the swing arc of arm 500 and vehiclestructural components 430. This maximum, uniform vertical motion alongthe entire length of the vehicle structural component between the ends430a and 430b also provides maximum, uniform heat transfer along thelength of the vehicle structural component.

Parallelogram linkage 502 includes an upper link 504 and a lower link506 each having a respective inner end 504a and 506a pivotally connectedto hub 406, and each having a respective outer end 504b and 506bpivotally connected to arm 500. Upper link 504 is shorter than lowerlink 506. Arm 500 moves along its travel path upwardly from tank 440through the noted given range of motion parallel to vertical axis 408and then continues to move upwardly through an upper range of motionwherein arm 500 swings in an arc 508 nonparallel to vertical axis 408.During the upper range of motion of arm 500 along swing arc 508, upperlink 504 pivots through a greater angle to dashed line position 510 thanthe angle of pivoting of lower link 506 to dashed line position 512.During the noted given range of motion, upper and lower links 504 and506 pivot through about the same angle from the respective solid linepositions shown to respective dashed line positions 509 and 511. Hub 406has an extended trunion 514 extending outwardly towards arm 500 andpivotally mounting inner end 504a of upper link 504.

Winch pulley 428, FIG. 35, is driven by a motor 520, FIG. 34, carried onsupport beam 414. In another embodiment, winch pulley 428 is externallydriven by a motor 522, FIG. 43, driving through belt 524 a flywheelassembly 526 to in turn rotate driveshaft 528. Motor mount 530 rests onplate 532 which also has a journal bearing 534 receiving driveshaft 528rotating therein. Plate 532 is mounted by blocks 536 and 538 on slidebar 540 to slide horizontally left and right therealong as controlled byshift lever 542. Leftward and rightward movement of motor mount 530 anddriveshaft 528 moves coupler 544 on the end of driveshaft 528 into andout of engagement with coupler 546 of winch pulley 428, to in turn drivethe latter.

In FIG. 44, arm 410 is oscillated by a crank lever 550 pivoted at 552and having at one end a roller 554 engaging the underside of arm 410,and having its other end driven by a rod 556 extending from eccentriclink 558 on rotary shaft 560 driven by motor 562.

In FIG. 45, rotary carousel 570 includes central hub 572 rotatable abouta vertical axis 574 and having a plurality of arms 576 pivotally mountedto the hub to pivot in a vertical swing plane about a horizontal pivotaxis 578, FIG. 46. A plurality of rigid stationary spokes provided bysupport beams 580 extend radially outwardly from the hub and areconnected by a circumferential support bar 582. The carousel rotates thearms from loading station 584 to coating station 586 to drip station 588to unloading station 590. One or more stacked vehicle structuralcomponents 592 are carried on arms 576. The arms are raised and loweredby a cable 594 extending around pulley 596 and driven by winch pulley598.

The loading station, coating station, drip station, and unloadingstation are all elevated above ground level. The vehicle structuralcomponents are stacked at ground level below the unloading station. Dripstation 588 includes a channel 600 for receiving excess coating liquidwhich is then recirculated by pump 602 back to tank 604 at coatingstation 586. Vapors are vented at 606. The outer end of arm 576 isstroked by lever 608, FIG. 47, pivoted at 610 and driven by cylinder612, to oscillate vehicle structural component 592 in coating liquid 614in tank 604. The carousel is driven to rotate by an external chain drive616 engaging spaced teeth 618, FIG. 48, along circumferential supportbar 582. A motor connection 620 drives a drive sprocket 622 to drivechain 624 around idler sprocket 626. Between the sprockets, chain 624engages and drivingly advances teeth 618 on circumferential bar 582 tothus rotate the carousel.

A stacking mechanism 630, FIGS. 49 and 50, is provided by an elevatorwhich raises and lowers vehicle structural components 592 at the loadingand unloading stations. The stacking mechanism has a pair of verticalupstanding sides 632 and 634 having respective carriages 636 and 638vertically slidable therealong. Cylinders 640 and 642 have extensibleand retractable plunger rods 644 and 646 with gear wheels 648 and 650 onthe end thereof which engage respective stationary toothed racks 652 and654 on respective sides 632 and 634. Gear wheels 648 and 650 also engagerespective toothed racks 656 and 658 on movable carriages 636 and 638.When plunger rods 644 and 646 are extended upwardly, gear wheel 648rotates clockwise along stationary rack 652, and gear wheel 650 rotatescounterclockwise along stationary rack 654, to thus respectively drivemovable racks 656 and 658 upwardly, and hence drive respective carriages636 and 638 upwardly to the respective dashed line positions 637 and 639shown in FIG. 50. The upward motion is aided by counterweights 660 and662 connected by respective cables 664 and 666 to respective carriages636 and 638 by pulleys 668, 670 and 672, 674. When carriages 636 and 638move upwardly, respective counterweights 660 and 662 move downwardly.The carriages have inwardly extending support shelves 676 and 678engaging the undersurface of the sides of vehicle structural component592.

The stacking mechanism is raised such that shelves 676 and 678 move torespective upper dashed line positions 677 and 679 and engage vehiclestructural component 592 and lift same off fingers 680, FIG. 49, ofhands 682 of arm 576, and/or arm 576 has a slight amount of overtravel,to provide the above noted disengagement. Shelves 676 and 678 are thenmoved horizontally rightwardly in FIG. 49 by respective cylinders 684and 686. Shelves 676 and 678 are mounted by respective bearings 688 and690 in horizontal tracks 692 and 694 on the inner sides of carriages 636and 638. The unloading and stacking sequence below the unloading stationis as previously described. When a given number of vehicle structuralcomponents are stacked, the stack is lowered onto conveyor belt 696 andthen horizontally transported from below the unloading station.

In FIG. 51, rotary carousel 700 has a central hub 702 rotatable about avertical axis and having an arm 704 pivotally mounted thereto to swingin a vertical plane about a horizontal pivot axis 706. Arm 704 is raisedand lowered by cable 708 driven by winch pulley 710. A combined loadingand unloading station 712, a wash station 714, a rinse station 716, anda coating station 718 are peripherally spaced around hub 702. Vehiclestructural component 720 is attached to arm 704 at combined loading andunloading station 712, and hub 702 is rotated clockwise to move arm 704to wash station 714 then to rinse station 716 then to coating station718 to coat vehicle structural component 720. Hub 702 is then rotated inthe opposite direction, i.e., counterclockwise, to move arm 704 back tothe combined loading and unloading station 712 for detachment. Anothervehicle structural component is mounted to the arm at station 712, andthe cycle is repeated. Coating station 718 includes a tank containingcoating liquid, as above. Arm 704 is moved downwardly at the combinedloading and unloading station 712 to engage vehicle structural component720, and the arm is then moved upwardly at station 712, and hub 702 isrotated clockwise. Arm 704 is moved downwardly and then upwardly at eachof stations 714, 716 and 718. Vehicle structural component 720 isattached and detached in a generally horizontal position at station 712,and is lowered at each of stations 714, 716 and 718 to a generallyhorizontal position.

In FIG. 52, the loading and unloading functions are split so thatstation 712 is the loading station, and station 722 is the unloadingstation. Hub 702 is rotated clockwise to unloading station 722, and thenrotated in the opposite direction, i.e., counterclockwise, back toloading station 712, and the cycle is repeated.

It is recognized that various equivalents, alternatives andmodifications are possible within the scope of the appended claims.

I claim:
 1. A manufacturing method for applying a coating to vehiclestructural frames having a longitudinal extent of a given length,comprising:providing a transport mechanism; providing a loading station;providing a coating station having a coating liquid; providing aunloading station; loading a vehicle structural frame to said transportmechanism at said loading station; transporting said vehicle structuralframe to said coating station, and moving said vehicle structural framethrough said coating station in a horizontal position such that saidlongitudinal extent of said vehicle structural frame is substantiallyhorizontal; transporting said vehicle structural frame to said unloadingstation and unloading said vehicle structural frame in a generallyhorizontal position below said unloading station; transportingadditional vehicle structural frames from said loading station throughsaid coating station to said unloading station and unloading saidvehicle structural frames and stacking each vehicle structural frame ina horizontal position on the vehicle structural frame therebelow toprovide a stack of horizontal vehicle structural frames stackedvertically and disposed below said unloading station.
 2. The methodaccording to claim 1 comprising stacking a plurality of said vehiclestructural frames below said unloading station, and upon completion ofsaid stacking, transporting the stack of vehicle structural frames frombelow said unloading station.
 3. The method according to claim 2comprising providing said loading station, said coating station, andsaid unloading station at ground level, providing an excavation belowground level at said unloading station, stacking said vehicle structuralframes in said excavation below said unloading station.
 4. The methodaccording to claim 2 comprising stacking said vehicle structural framesat ground level below said unloading station, and elevating said loadingstation, said coating station, and said unloading station above groundlevel.
 5. A manufacturing method for applying a coating to vehiclestructural frames having a longitudinal extent of a given length,comprising:providing a transport mechanism; providing a loading station;providing a coating station having a coating liquid; providing anunloading station; providing a stacking station below said unloadingstation; attaching a first vehicle structural frame to said transportmechanism at said loading station; transporting said first vehiclestructural frame to said coating station, and moving said first vehiclestructural frame through said coating station in a horizontal positionsuch that said longitudinal extent of said first vehicle structuralframe is substantially horizontal; transporting said first vehiclestructural frame to said unloading station; detaching said first vehiclestructural frame from said transport mechanism; lowering said firstvehicle structural frame in a horizontal position at said stackingstation below said unloading station; attaching a second vehiclestructural frame to said transport mechanism at said loading station;transporting said second vehicle structural frame to said coatingstation, and moving said second vehicle structural frame through saidcoating station in a horizontal position such that said longitudinalextent of said second vehicle structural frame is substantiallyhorizontal; transporting said second vehicle structural frame to saidunloading station; stacking said second vehicle structural frame in ahorizontal position on said first vehicle structural frame; detachingsaid second vehicle structural frame from said transport mechanism;lowering said stacked first and second vehicle structural frames in ahorizontal position at said stacking station below said unloadingstation; attaching a third vehicle structural frame to said transportmechanism at said loading station; transporting said third vehiclestructural frame to said coating station, and moving said third vehiclestructural frame through said coating station in a horizontal positionsuch that said longitudinal extent of said third vehicle structuralframe is substantially horizontal.
 6. The method according to claim 5comprising providing a stacking mechanism at said stacking station,raising said stacking mechanism to engage said first vehicle structuralframe at said unloading station and lift said first vehicle structuralframe from said transport mechanism, and then moving said transportmechanism horizontally, to detach said first vehicle structural framefrom said transport mechanism at said unloading station.
 7. The methodaccording to claim 6 comprising lowering said stack mechanism and movingsaid stacking mechanism horizontally to return to an alignment positionto receive said second vehicle structural frame such that said firstvehicle structural frame engages said second vehicle structural frame atsaid unloading station and lifts said second vehicle structural framefrom said transport mechanism, and moving said transport mechanismhorizontally, to detach said second vehicle structural frame from saidtransport mechanism, lowering said stacking mechanism and moving saidstacking mechanism horizontally to return to an alignment position toreceive said third vehicle structural frame such that said secondvehicle structural frame engages said third vehicle structural frame atsaid unloading station and lifts said third vehicle structural framefrom said transport mechanism, and moving said stacking mechanismhorizontally, to detach said third vehicle structural frame from saidtransport mechanism, repeating the above steps to provide a plurality ofhorizontally extending vehicle structural frames stacked vertically atsaid stacking station below said unloading station.
 8. The methodaccording to claim 5 comprising providing said transport mechanism witha rotary carousel having a central hub rotatable about a vertical axisand having at least one arm thereon for carrying one or more vehiclestructural frames;transporting said vehicle structural frame from saidloading station to said coating station to said unloading station byrotating said hub; moving said arm downwardly at said loading station toengage said vehicle structural frame, and moving said arm upwardly atsaid unloading station to lift said vehicle structural frame and carrysaid vehicle structural frame during said rotating of said hub, movingsaid arm downwardly and then upwardly at said coating station, andmoving said arm downwardly at said unloading station to disengage saidvehicle structural frame as said stacking mechanism engages said vehiclestructural frame, and moving said arm upwardly at said unloading stationand rotating said hub to move said arm to said loading station.
 9. Themethod according to claim 8 comprising moving said arm downwardly atsaid unloading station until said stacking mechanism engages saidvehicle structural frame, and continuing moving said arm downwardly witha slight amount of overtravel to disengage said vehicle structuralframe, moving said stacking mechanism horizontally, moving said armupwardly at said unloading station and rotating said hub to move saidarm to said loading station.
 10. The method according to claim 8comprising moving said arm downwardly at said unloading station to agiven position, moving said stacking mechanism upwardly and engagingsaid vehicle structural frame and lifting said vehicle structural framefrom said arm, moving said stacking mechanism horizontally, moving saidarm upwardly at said unloading station and rotating said hub to movesaid arm to said loading station.